Question: What are the advantages and disadvantages of using the fuse ROM option of CY7C656XX instead of an external EEPROM?
- The fuse ROM inside CY7C65630 can be set at the factory according to the customer’s specifications. You can order the parts with the fuse ROM preprogrammed with your vendor ID (VID) / product ID (PID) and configuration options.
- When you order the parts with this option, your configuration is the default of the chip and no EEPROM is required. All the configurations that are possible with an EEPROM are possible with the fuse ROM option.
- The Fuse ROM option is not commonly advised because of the following reason. Factory programming of the fuse ROM is labor-intensive, involving a substantial amount of work by various teams, including the Price-to-Earnings (PE) Team, the Autoline Manufacturing Team, and the Testing and Validation Team. In order to be a profitable transaction, the customer would need to share the nonrecurring engineering (NRE) expenses with us.
- Also for this reason, it is feasible for both Cypress and the customer to choose the Fuse ROM option only if the order is substantially large.
- Once the customer uses the fuse ROM option, the part can be used only by that specific customer. Therefore, the customer would need to place all the orders as non-cancelable, non-returnable (NCNR).